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<table width="100%" summary="page for RScompetition"><tr><td>RScompetition</td><td style="text-align: right;">R Documentation</td></tr></table>

<h2>Competition between two biotypes</h2>

<h3>Description</h3>

<p>To assess the competitive ability between two biotypes of <em>Lolium rigidum</em>, one resistant to glyphosate
and the other a sensitive wild type, the density of resistant and sensitive biotypes was counted after
germination.
</p>


<h3>Usage</h3>

<pre>data(RScompetition)</pre>


<h3>Format</h3>

<p>A data frame with 49 observations on the following 3 variables.
</p>

<dl>
<dt><code>z</code></dt><dd><p>a numeric vector with densities of the resistant biotype (plants/m2)</p>
</dd>
<dt><code>x</code></dt><dd><p>a numeric vector with densities of the sensitive biotype (plants/m2)</p>
</dd>
<dt><code>biomass</code></dt><dd><p>a numeric vector of biomass weight (g/plant)</p>
</dd>
</dl>



<h3>Details</h3>

<p>A hyperbolic model (Jensen, 1993) is describing the data reasonably well.
</p>


<h3>Source</h3>

<p>The dataset is from Pedersen et al (2007).
</p>


<h3>References</h3>

<p>Jensen, J. E. (1993) Fitness of herbicide-resistant weed biotypes described by competition models, 
<em>Proceedings of the 8th EWRS Symposium, 14-16 June, Braunschweig, Germany</em>, 
<b>1</b>, 25&ndash;32.
</p>
<p>Pedersen, B. P. and Neve, P. and Andreasen, C. and Powles, S. (2007) Ecological fitness of a glyphosate 
resistant <em>Lolium rigidum</em> population: Growth and seed production along a competition gradient,
<em>Basic and Applied Ecology</em>, <b>8</b>, 258&ndash;268.
</p>


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